(Our store has a “4 for 3” offer on greeting cards. Individual prices are clearly labelled on the backs of the cards to prevent confusion. A customer comes in and looks at the sign for a moment before approaching the counter.)

Customer: “That means four for £3, right?”

Me: “No, it’s four for the price of three.”

Customer:*laughs and looks at me as if I’m stupid* “Yeah, that’s what I just said.”

(I try to explain that she’s incorrect but she wanders off, chooses four cards and comes back to the till again, so I ring up her total.)

Me: “Okay, that’ll be £9.99, then, please.”

Customer: “What?! But you said they were four for £3!”

Me: “No, I said they were four for the price of three. Sorry if there was any confusion.”

Customer: “Well, then, I don’t want them. I didn’t want four in the first place. I only got four because you told me it was four for £3. I wanted two. Take two off.”

Me: “Okay, which would you like to take off?”

Customer: “I don’t know! Let me think.”

(Our tills don’t allow item voids; you have to void the entire transaction, so it’s always painful when someone changes their mind. I cancelled it and started over, but then she proceeded to take a solid minute or so debating which cards she wanted to keep while a long queue built behind her, and then made sure to give me a filthy look on the way out.)